Do they test all the food coming into the country?

Risk food (100 per cent tested): These foods have a medium to high level of risk to the public, and tests carried out depend on the type of food.

Surveillance food (5 per cent of food lines tested): All other foods not classified as a risk food. These foods have less likelihood of being dangerous to the public, but if a surveillance food fails inspection, the inspection levels are increased.

Food import compliance agreement: Importers can apply for an agreement that their food does not need to be inspected every time it arrives in Australia. If the Department of Agriculture agrees that their food management systems are satisfactory, the imports can be fast tracked at the borders.

Is fruit in one of the categories?

All food falls into one of those categories. Most fruits are in the surveillance category, so 5 per cent of fruit lines coming into the country are inspected, unless the company has a Food Import Compliance Agreement and can sidestep inspection.

Where do we get food from?

Australia's biggest importer in dollar terms is its eastern neighbour, New Zealand. Australia shares a government agency with New Zealand that writes the rulebook on food safety for both countries so we do not test each other's food imports.

China is Australia's third largest importer but its food is tested more than any other origin country. In one year, Australia inspected 2,706 lines of food imported from China – 9 per cent of total food inspections.

Chinese imports were analysed for dangerous chemicals, contaminants and microorganisms (usually forms of bacteria). They had a 100 per cent compliance rate for all food tested for microbial agents from July 2013 to June 2014, however they had only a 95 per cent compliance rate when tested for chemicals like pesticides.

How could they miss a hepatitis A contamination of a fruit?

Australia does not routinely test for hepatitis A, or any other virus. The inspectors test for microorganisms, or bacteria, like E.coli and salmonella, but these are mainly tested in animal products like seafood.

FSANZ has advised that it is extremely difficult to test for viruses in food as they're usually present at extremely low levels that aren't easily detectable with current methods of analysis.

Salmonella, E. coli and listeria top the list of microbial agents the Department of Agriculture routinely checks for.

What do they test for in fruits?

Fruits are mainly tested for poisonous pesticides.

How do they test?

All foods are checked to make sure their labels comply with Australian regulations and there's a visual check to assess whether they are safe. Then the food gets sent off for tests based on its risk level.

If it is already a high risk food, inspectors wait for the food to pass the test before the food is released for sale. With everything else, inspectors take samples, let the food into the country, and only take action if the tests of the samples reveal problems with the food.

Are the food importers required to meet any standards beyond the origin country's requirements?

Yes. The imports are supposed to comply with requirements laid out in the Australian New Zealand Food Standards Code.

What if they fail?

The food product can be treated, re-exported or destroyed. The food can also be recalled. If more shipments of the failed food are sent to Australia, 100 per cent are inspected for compliance with the food standards until the long-term safety of the product is established.

Are any foods banned entirely?

Yes. One example is that oysters from particular regions are not allowed into Australia at all, so if oysters reach Australia's borders and do not have a certificate of origin, they are not allowed through.